package com.ruoyi.web.controller.monitor;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
import java.util.TreeSet;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisCallback;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.security.access.prepost.PreAuthorize;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import com.ruoyi.common.constant.CacheConstants;
import com.ruoyi.common.core.domain.AjaxResult;
import com.ruoyi.common.utils.StringUtils;
import com.ruoyi.system.domain.SysCache;

/**
 * 缓存监控控制器
 * 提供对Redis缓存的监控和管理功能，包括查看缓存信息、获取缓存键值、清空缓存等操作
 *
 * @author ruoyi
 */
@RestController
@RequestMapping("/monitor/cache")
public class CacheController {
    @Autowired
    private RedisTemplate<String, String> redisTemplate;

    private final static List<SysCache> caches = new ArrayList<SysCache>();

    /*
      初始化系统缓存配置
      该方法用于初始化系统中各种功能模块的缓存配置，包括用户登录、系统配置、
      数据字典、验证码、防重提交、限流处理和密码错误次数等关键业务缓存。
      无参数
      无返回值
     */
    {
        // 添加用户登录相关的缓存配置
        caches.add(new SysCache(CacheConstants.LOGIN_TOKEN_KEY, "用户信息"));
        // 添加系统配置相关的缓存配置
        caches.add(new SysCache(CacheConstants.SYS_CONFIG_KEY, "配置信息"));
        // 添加数据字典相关的缓存配置
        caches.add(new SysCache(CacheConstants.SYS_DICT_KEY, "数据字典"));
        // 添加验证码相关的缓存配置
        caches.add(new SysCache(CacheConstants.CAPTCHA_CODE_KEY, "验证码"));
        // 添加防重提交相关的缓存配置
        caches.add(new SysCache(CacheConstants.REPEAT_SUBMIT_KEY, "防重提交"));
        // 添加限流处理相关的缓存配置
        caches.add(new SysCache(CacheConstants.RATE_LIMIT_KEY, "限流处理"));
        // 添加密码错误次数统计相关的缓存配置
        caches.add(new SysCache(CacheConstants.PWD_ERR_CNT_KEY, "密码错误次数"));
    }


    /**
     * 获取Redis服务器信息
     * 包括服务器基本信息、命令统计信息和数据库大小
     *
     * @return AjaxResult 包含Redis服务器信息的结果对象
     * @throws Exception 执行Redis命令时可能抛出的异常
     */
    @PreAuthorize("@ss.hasPermi('monitor:cache:list')")
    @GetMapping()
    public AjaxResult getInfo() throws Exception {
        // 获取Redis服务器基本信息
        Properties info = (Properties) redisTemplate.execute((RedisCallback<Object>) connection -> connection.info());
        // 获取Redis命令统计信息
        Properties commandStats = (Properties) redisTemplate.execute((RedisCallback<Object>) connection -> connection.info("commandstats"));
        // 获取当前数据库键的数量
        Object dbSize = redisTemplate.execute((RedisCallback<Object>) connection -> connection.dbSize());

        Map<String, Object> result = new HashMap<>(3);
        result.put("info", info);
        result.put("dbSize", dbSize);

        // 处理命令统计信息，提取命令名称和调用次数用于图表展示
        List<Map<String, String>> pieList = new ArrayList<>();
        commandStats.stringPropertyNames().forEach(key -> {
            Map<String, String> data = new HashMap<>(2);
            String property = commandStats.getProperty(key);
            data.put("name", StringUtils.removeStart(key, "cmdstat_"));
            data.put("value", StringUtils.substringBetween(property, "calls=", ",usec"));
            pieList.add(data);
        });
        result.put("commandStats", pieList);
        return AjaxResult.success(result);
    }

    /**
     * 获取预定义的缓存名称列表
     *
     * @return AjaxResult 包含缓存名称列表的结果对象
     */
    @PreAuthorize("@ss.hasPermi('monitor:cache:list')")
    @GetMapping("/getNames")
    public AjaxResult cache() {
        return AjaxResult.success(caches);
    }

    /**
     * 根据缓存名称获取匹配的缓存键列表
     *
     * @param cacheName 缓存名称前缀
     * @return AjaxResult 包含匹配缓存键列表的结果对象
     */
    @PreAuthorize("@ss.hasPermi('monitor:cache:list')")
    @GetMapping("/getKeys/{cacheName}")
    public AjaxResult getCacheKeys(@PathVariable String cacheName) {
        Set<String> cacheKeys = redisTemplate.keys(cacheName + "*");
        return AjaxResult.success(new TreeSet<>(cacheKeys));
    }

    /**
     * 获取指定缓存键的值
     *
     * @param cacheName 缓存名称
     * @param cacheKey 缓存键
     * @return AjaxResult 包含缓存键值信息的结果对象
     */
    @PreAuthorize("@ss.hasPermi('monitor:cache:list')")
    @GetMapping("/getValue/{cacheName}/{cacheKey}")
    public AjaxResult getCacheValue(@PathVariable String cacheName, @PathVariable String cacheKey) {
        String cacheValue = redisTemplate.opsForValue().get(cacheKey);
        SysCache sysCache = new SysCache(cacheName, cacheKey, cacheValue);
        return AjaxResult.success(sysCache);
    }

    /**
     * 清空指定缓存名称下的所有缓存
     *
     * @param cacheName 缓存名称前缀
     * @return AjaxResult 操作结果
     */
    @PreAuthorize("@ss.hasPermi('monitor:cache:list')")
    @DeleteMapping("/clearCacheName/{cacheName}")
    public AjaxResult clearCacheName(@PathVariable String cacheName) {
        Collection<String> cacheKeys = redisTemplate.keys(cacheName + "*");
        redisTemplate.delete(cacheKeys);
        return AjaxResult.success();
    }

    /**
     * 清空指定缓存键的缓存
     *
     * @param cacheKey 缓存键
     * @return AjaxResult 操作结果
     */
    @PreAuthorize("@ss.hasPermi('monitor:cache:list')")
    @DeleteMapping("/clearCacheKey/{cacheKey}")
    public AjaxResult clearCacheKey(@PathVariable String cacheKey) {
        redisTemplate.delete(cacheKey);
        return AjaxResult.success();
    }

    /**
     * 清空所有缓存
     *
     * @return AjaxResult 操作结果
     */
    @PreAuthorize("@ss.hasPermi('monitor:cache:list')")
    @DeleteMapping("/clearCacheAll")
    public AjaxResult clearCacheAll() {
        Collection<String> cacheKeys = redisTemplate.keys("*");
        redisTemplate.delete(cacheKeys);
        return AjaxResult.success();
    }
}
